The radio-controlled aircraft (RC aircraft) has become popular in recent years. There are more and more related groups, leagues, shows or competitions where people are enthusiastic to participate. With the development of technology, the radio-controlled aircraft can fly with a camera for shooting aerial footage and photos. In general, there have two main types of conventional radio-controlled aircraft. One is the radio-controlled helicopter in which lift and thrust are supplied by spinning or tilting two propellers (blades); and the other one is the radio-controlled multicopter which has more propellers than the radio-controlled helicopter, and control of motion is achieved by varying the rotational speed of each propeller to change the thrust and torque produced by each.